Quenching press



Jan. H', 195() o. F. BAUER 2,49%984 QUENCHING PRESS Filed Feb. 8, 1945 8Shets-Sheet l Eig? 17 L 3 nvcntor @LIVER E BAUER.,

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Jan. 17, 195o o. F. BAUER 2,494,984

QUENCHING PRESS Filed Feb. 8, 1945 8 Sheets-Sheet 2 Bnventor K GLM/BQ F:BAUER @7,2 am,

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Jam. 17', 1950 o. F. BAUER. 2,494,984

QUENCHING PRESS Filed Feb. 8, 1945 8 Sheets-Sheet 4 W) nventor Jan. 17,1950 o', F BAUERv 2,494,984

QUENCHING PRESS Filed Feb. 8, 1945 8 She'ets-Sheet 5 Jr206 54 2/6 I I o?aow/208 Z'snventor @Ln/EQ, f? BAUER Gttorneg O. F. BAUER QUENCHING PRESSJan. W', 950

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8 Sheets-Sheet 6 Filed Feb. 8, :1945

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fm Lw Cttorneg Jan. l?, 1950 o. F. BAUER 2,494,984

QUENCHING PRESS Filed Feb. 8, 1945 8l Sheets-Sheet 7 Jan.. R7, 195 o. F.BAUER 2,494,984

QUENCHING PRESS Filed Feb. 8, 1945 s sheets-sheet 8 A Snvcutor @wwwa ffBAUER handling. 'There has been no control over the volume or rate offlow of the quenching medium over the work after the initial quench.Thus the molecular structure of the hardened workpiece has dependedalmost entirely on the volume of quenching liquid that can be owed overthe work in the rst few seconds o the quenching operation, that is, inthe period of the initial or drastic quench. With the present inventiona quenching press has been provided in which it is possible to controlvolume of the flow of the quenching fluid at all stages of the quenchingoperation. Thus, with the new press it is pdssible to obtain, forinstance, a fast, drastic quench until the critical point of thehardening temperature is reached, then a slow quench to stabilize themolecular structure of the work and cool the metal without causingdistortion, and then a quick cooling quench to bring the job to a pointwhere the operator can handle it. In the press of the present invention,it is also possible to insure for each particular job a volume ofquenching liquid suitable for hardening that particular job. Too great avolume might in a particular job cause distortion, while in another casethat same volume might be just what isidesired.

In the press shown in the drawings, the volume of the quenching liquidat various stages of the quenching operation is controlled by threesolenoid-operated valves, and the solenoids are in turn controlled bythree electric timers. Each valve permits a different amount of liquidto flow to the work. When all three valves are open the maximum volumeof liquid flows to the work. Manually adjustable controls are providedby adjustment of which various combinations of valves may be preselectedfor operation in a particular order. Other adjustable controls areprovided by which the timers may be adjusted to control the times duringwhich each combination of valves is to operate. In this way, the volumeof the quenching uid flowing over the work during successive stages ofthe quenching operation may be predetermined and controlled.

In some prior types of quenching presses, controls have been provided,which cause the upper die to be disengaged from and moved clear of thework automatically at the end of the hardening operation. In the newquenching press of the present invention, besides the controls alreadydescribed, other controls are provided whichA permit complete automaticoperation of the press from the moment the workpiece, which is to behardened, is placed on the bracketin loading position until the hardenedarticle is returned by the bracket to loading position again, ready forremoval by the operator. When the operator presses the starting button,he starts a motor which moves the bracket to swing the work intooperating position. When the bracket reaches operating position, throughlimit switches, the motor is stopped, and the piston carrying the upperdie is actuated, causing it to descend. Through a control cam mounted onthe piston, the rate of downward movement of the piston is controlled.In the iirst part of its downward movement, they piston descends fast,but as the upper die approaches the work, the piston is automaticallyslowed down to prevent the upper die from hitting the hot workpiecehard. When the upper die has, however, engaged the workpiece, fullpressure is put on again to holdthe work securely during quenching. Thenthrough the tripping of a limit switch the quenching liquid is turned onand iiowed around and over the work in the volume and time cyclepredetermined by the settings of the various controls already described.When the quenching cycle is complete, through suitable electrical trips,the valve, which controls the upper-die piston, is reversed and thepiston is moved upwardly to disengage the upper die from the work. Whenthe piston reaches its uppermost position, a limit switch is tripped andthe bracket motor is restarted. The bracket is then swung out to movethe work to loading position. The operator can then remove the nowhardened gear and place a new heated workpiece in its place.

In the accompanying drawings:

Fig. 1 is a fragmentary front elevation of a quenching press builtaccording to a preferred embodiment of this invention, the work beingshown in out or loading position;

Fig. 2 is a vertical sectional view of this quenching press, the sectionbeing taken from front to rear;

Fig. 3 is a sectional view taken at right angles to the view of Fig. 2and on a somewhat enlarged scale, showing the upper die and itsassociated parts and the swinging bracket on which the lower die ismounted, the upper die and the piston, which operates the same, beingshown in their uppermost or inoperative positions;

Fig. 4 is an enlarged vertical sectional view of a typical set-up,showing the hardening of a bevel gear, and showing the upper and lowerdies used for the purpose in operative engagement with the work, withthe upper die at the limit of its downward movement;

Fig. 5 is a fragmentary detail View showing in section part of themechanism for operating the swinging bracket which carries the lowerdie;

Fig. 6 is a detail View showing the cam and the mechanism associatedtherewith which operate to control the Aspeed of downward movement ofthe upper die and of the piston which moves the same;

Fig. 7 is a fragmentary sectional view, showing the mechanism forselecting whether the press is to be automatically or manually operated;

Fig. 8 is a view at right angles to Fig. 7, showing further details ofthese parts;

Fig. 9 is a fragmentary enlarged sectional view similar to Fig. 4 butshowing somewhat diierent forms of upper and lower dies for holding adifferent type of gear and showing also a somewhat different type ofmechanism for centering and holding the work against radial distortion;

Fig. l0 is a fragmentary plan view of the lower die used in themechanism of Fig. 9;

Fig. 11 is a diagram of the pneumatic circuit of the press andillustrating its mode of operation; and

Fig. 12 is a diagram showing one way in which the press may be wiredelectrically to perform its functions.

. Reference will now be had to the drawings for a more detaileddescription of the invention.

The quenching press shown has a frame consisting of a base portion 20and an upright or column portion 2|. These may be, as shown, integralwith one another. Secured to the ribbing of the upright portion 2l, asby means of screws 23, is an open-ended 4casing or housing 24 (Figs. 2and 3). To the lower end of this casing there is secured by screws 26 abearing or guide member 25. The upper end of the casing is closed by anend plate 21, which is secured to the casing by screws 28, and by a capmember 3D which is secured in a central opening, formed in the endlhroueh the ,mechanism described, the arms 9| can be oscillated abouttheir pivotdpins 92 to move the plate B2 and the parts supported therebyfrom operating to loading position and vice versa. The arms 9|, linkmembers |02 and arms 93 are shown in full lines in Fig. 2 in thepositions they occupy when the plate 82 is in operative position, whilethey are shown in dotted lines in the positions they occupy when theplate 82 is in loading position. In this movement from loading tooperative position and return, the plate 82 is guided by pins |05 whichproject from opposite sides of the plate 82 and which engage in arcuateslots |06 (Fig. 2) formed in the base portion 20 of the press.

In operative position, the bracket or plate 82 is adapted to rest onplane-surfaced seating portions and I| (Fig. 4) of a seating member H2which is secured by screws |I3 to the base portion 2E) of the machine.To hold the lower die accurately in alignment with the upper die, whenthe bracket or plate 32 is in operative position, cooperating -male andfemale centering members ||5 and H9 are provided. The male member H5 issecured by means of screws H6 in a recess formed centrally in theunderface of the plate 82. The female member H9 is secured by screws ina recess formed centrally in the upper face of the seating member H2.The member H5 is formed with an external conical seating surface H1which is adapted to be engaged with the internal conical seating surfaceH8 of the member H9.

Fig. 4 shows the positions of the .parts when the piston 34 is in itslowermost position and the upper die 45 is in operative engagement withthe work. Before the bracket 82 can be swung to loading position, it isnecessary to lift the centering member H5 out of engagement with thecentering member H9. To this end, an angle iron piece 'I6 (Fig. 3) isprovided. This angle iron piece is secured to a post or stud 11 thatprojects upwardly through a hole formed centrally in the cap member 30,and that engages a stop-screw 19 that is threaded adjustably into a lug18. The lug 18 is formed integral with the bar or strap 95 which, asalready described, connects the two arms 93. As the piston 34 approachesthe upper end of its stroke, its head 36 strikes the angle piece 16 andthrough the stud 11 and stop-screw 19 moves the arms 93 and pins 92upwardly, lifting the centering member H5 of its seat. The stop-screw 19permits adjustment of the point where the motion of the piston 34 liftsthe bracket 82 off its seat.

The bar 95 has an angle plate 88 secured to its front face. This angleplate is adapted to engage the plunger of a limit switch 360 to closethis switch Iand start the motor 96. Thus, the motor 96 is startedautomatically t-o swing the bracket -82 and the work to loading positionwhen the :piston 34 reaches its uppermost position, as will hereinafterbe described more particularly. The limit switch 350 is mounted on apost y89 which is secured in the end plate 21.

When the bracket 82 is returned to operating position, the arms 9| bringthe centering member I I5 over the centering member H9 and when thepiston 34 starts to move downward, the cooperating conical portions Iand I8 yof the centering members engage one another and align the lowerdie accurately with the upper die.

The pressure fluid for operating the pistons 34 and E9 is supplied tothe machine from any suitable source, for instance, an external source Sthrough piping denoted diagrammatically at |20 inFig. 11.

One of the features of the press illustrated is that pressure i-smaintained on the under side of the head 36 of the piston 34 not onlyduring upward movement of the piston but also during downward movementof the piston. The amount of pressure on the underside of the pistonhead during the downstroke is, of course, less than the amount ofpressure on the upper side of the piston head during this stroke, and isalso less than the Iamount of pressure on the underside of the pistonhead on the upstroke of the piston. The amounts of pressure on the twosides of the Apiston head 34 are regulated by pressure reducing valves|25, |60, and and by blow-off valves |31 and |91. A shuttle valve |2|,which is reciprocable in a valve casing |22, serves to maintain pressureon the under side of the piston during its down-stroke, Ias willhereinafter more paricularly be described.

The reducing valves |25, |50, and |80 may be 0f any standard or suitableconstruction and preferably are all made alike. The structure of onlyone of these valves, |25, need, therefore, be described here. In thisvalve, the valve member |33 is secured to a diaphragm |32. The valvemember is normally pressed open by a eoil spring |31, the tension ofwhich can be adjusted by a screw |30. A coil spring |34 serves tocounteract in part the action of the spring |3| and tends to force thevalve member |33 toward closed position. By suitable adjustment of thescrew |30, the amount of air-pressure required to close the valve member|33 can be adjusted, that is, the amount of pressure in the line |26 canbe predetermined. In similar way the valves |60 and |80 can be adjustedby the screws |62 and |63 to control the amounts of pressure in thelines |6| and |8I.

A gauge |35, which communicates with the duct |26 through a duct |36,may be used in the adjustment of the valve |25, while a gauge |11, whichcommunicates with the duct |8I through the duct |82, is used inadjustment of the valve |80.

The blow-olf valves |31 and |91 may be of any standard yor suitableconstruction and preferably are alike in structure. The blow-oli valve|31 may consist, for instance, of a ball valve member |39, which isnormally held in closed position by a coil spring |40, the tension ofwhich may be adjusted through a knurled nut I4I that threads into thevalve casing. Blow-off openings |42 are drilled in opposite sides of thecasing.

The direction of movement of the piston 34 is controlled by threesolenoid operated valves |43, |14, and |15. The valve |43 is a normallyopen valve while the valves |14 and |15 are normally closed valves.

An adjustable throttle valve |89 governs the normal speed of thedownstroke of the piston 34, while a needle-Valve |83 controls the speedof the downward movement of this piston in the part of its downstrokejust before the upper die hits the hot workpiece. 'Ihe openings of thevalves |88 and |89 may be adjusted by the handwheels |9| and |92,respectively. The `press may be manually or automatically operated. Athree-way valve |48, which is manually adjustable, is provided to permitthe operator to preselect the mode of operation of the press. In thepositions of the parts shown in Fig. 1l, the pressure fluid fiows fromthe duct |20 into the duct |23 and thence through 10 :theI reducing.fi/faire lzaand. 1.a duety |20.V into., .the .fisrcarriedlbynne:of...therank,p1ates. 10U-.engages casing.l2Zottheshuttleralye. l2 I. the .plu-neer of wthelinnt switch 348 and.closes Thelshuttle :Valveiihasga stem5portgion Whichyis that limitswitch. This pauses the s olenoiclsd |46, 'mrovded-Wfith twospaoedgperipheral groovesA |66 d10, ancl1|1|` to beenergized, as will,hereinafter and |61, and with..a. `nenlargedhead|60 which f5 ...bedescribed, and4 the-:valve |434is closed, .while forms-. apistonthat isAreoiprooable ina cylinder the valves;l |14a nd. |1,5,-,are opened.Thisallows ,|60 formed in'theya'lveoasingfl. theair under.1 pressuretoow fromthe. line |23 ;-Fromethe duct -|26ythepressureluidiows.throughthe reducing valve |00, the Vducts |8I througha `duct |21Vboth;intola duct |28 and ...and |82, and.,thel.valife |15 into-.theduot|83. around thegroovegl inthe valve stem. This ,i0 .Thencewitgowsfboth/throughthe valve |14`A and groove communicatesfwthea duety|29. Thepresthe duct [84andthrough the duct'` |85, the needle @sureuidilowingfinto the-duct |28 holdsthevalve valve |86, and the duct |81,into the duct.|.88. in-,the position shown. Erom.theduct IZSthe Thisduetcommunioatesthrough.the manually pressure fluid flows .thnoughmhepipinguSmand .adjustableihrottle .valve |80 andthe duet. |90I Ycluot10tothe underfsidezfacegof.theheadof 5 with thepiping lthatleadsltothenpper vend ,the piston .34. The pressiureonthe underrfaoe of of theloy1inder,..+l. .the piston isrof course,'controlledfatthistimebylThepressureuuid.also.acl:sth1ro11gh the ,duct

the reducing-` ValveJ 25,-and relief, valve! 31. |49, thethree-:Wayyalve |48, and the,line,l,41

.At this ytime,.the uppenfae off, the piston head on the-under 'faoe ofythe pistonportion |153v of AAVSlison. exhaust;throughhegpipe 61,(-Figs.A 3l andi., 20,the.shuttle,.valve |2|,toj.orce this valveupwardly,

,11),` the duot |5| Whichfcommunicates with this Vfor ,the under.faoegof. this piston portion .468. has .,pipe, thesolenoid-operated'-va1ve.1|43,and.the argreaterareathanitsuppenface..The airabove .,:d-uctfl44to.theppenairthefsolenoidllllfwhioh ,thepiston |68 Vthen..exhausts through -blow'foff operatesthevalye.143,;,being5atthistimeeenopening.| 1-9. Theyresultisthattheshuttlevvalve ergized and.,the,.va1ve,member |45 being open. f 53|2|olos`esolr` thaonneotion. between Atheducts -Atthistiine,,alsothelower,endbf.theeylinolerm |21 and.,|29 andoQnneCtsthe,.i-I.1e,.69with the ,|09 is on exhaust throughjhe, line.|41,.,the; manduet |95 through .the. ,duct |29, the d-uct,|94, ,and`ually operable. threeeway. valve. 148.and theduct thegroove |61 in.`the. s,tenr1. of the shuttle valve |49 whioheonneots.witlrthe duct` |5that, leads .|2l. ,The duct. l|95.connf :otsthrough.theduot L.to theo.pen .so1enoid:operated Valve |43. 330 |86 wgththe adjustable reliefValve |91the.,ba ll At this.time alsothe upperend ,of the pisto ,|.S8Kof`which isnormally heldseated, by.,the c oil ..60 is v0.11Supplyfbeirigonneted .-lli/'ith@the` duct spring lwhose, pressure canbe. .adjusted bythe |23 through ductg12, .adifferentiallrelief valve nut200 which threads intothe valvebasing. ,150, Vthe 'cheek Valve|156,.theduotstandl-ll, ',Thus through,settngoithe reliefyalve,[91,pres- {and-thereducing valveJB. Vmug-,sure -oan'be exertedonithe,underiaoeofthe .The diierentialrelief.,valve. |50.may. beofanypiston head 36 during. the .gdownstroke of the ...suitable orstandardoonstruction. .As shownthe ypiston.

the .diaphragm I54'that Carries the yalyeQmember. ,240 ,and l6). LInthis ,box ,are `4mounted two ,.lmiit .The...prSSu1Te..i11...th. 11115.1.5! cooperates with A`switches 206 and 2.01 Whoseplungersf208andi2081 the pressure ofthespring `|523 `to holdthellralvelare `oppositely disposed ,to `.one another. The ..me mber.|.52closed.AThe,,pressurefluid therefore plungers are adapted tolbe operated by,a,bell `jows. from V.the duct 55, througlrtheheok..x/:alve cranklever 209vwhich., is piizoted .at '2 0V in ,the l156.OpeliligthebalLmerlberglSLQLthat i/...ali/e45 ,120x205 Theireeendf of this bellcrankdever againstthe Ynesstance of .the ,spring |58, 2.and extendsvbetween the. two plungers H2,00a1,1,d2081.

.'thenoe.through.the lduot |59 and,.theialye"|50 At its Aopposite end,thebell-crank lever ispivot- "into 'theiline 12. lally connected. by,means of thepin. 2U with@ 'The `described andillustrated positionsgarethe ,bai-.2|2. Thisbar is carried lby.a'1.i1.11\2 .213..Wl1.i2h`positions whichtherparts of theppneuinatic sysfgojspivotallyconneoted...at. oneendywththe ha? tem occupy'when thecpistonisin itsuppermost .by means of the pin. 2|4v` and Whiohilspivotatlly nposition,showningFigS. `'.'Ihepistorr60.is, howmounteolat itscppositeendhy .meansof lthepn zever, always on pressure, bothduring theyupand 2t5 onthe.boXj205. AThere is.. a' braktll @dftghe-down --strokes of rthegpistonV34. The Valve justably secured to the bar 2|2 by means ofa,set

l 50 `permits relief of the linefrom'iexoesspressure ,55 screw. 2 |1Rottal-,ably .mounted in the projecting l`when the-piston134=`-lsinf-thewdown positionand arm of this bracket isarollerjl whioh is,adapted f the expander is engaging fthe *segments 781 5to .to engagethe` cam` trakjfolimed 011th@ periphery lgrip the bore of the-work.lfIfitisfouncttliay'for frof, mecam membern52. YThe. rollerjgZl'lsresil- -any given type of lwork-*to Lbehardened'a reduced -iently heldin-engagement withthe Camtraok gripping pressure` inv the bore`during`lhardening=-zgsu by .a coil springllawhichis. intCIDQSed-betWeenis desirable, the'pressurein theflline 12.-.can alwaysv the ribbing,2,20V ofthe columnz Landthepar; 2 l2.

i be lowered byuse of thefbleeder: valve 20| which V`V,Intlle,uppermostpositionof;thepistQni34. 12.119 is-connectedfwiththe line12byztheduel-,2203. ,camsurfaoe 52ishaboyeand--out oioontat with`The'bleedervalvefincludes:axball member-#204 the roller 2|8 as shown indotted lines' 521 which can be clamped-shut'by-.assureur-membere65.Fig..6. In this position,.the. springZlS acting :202' thatthreads-into;thevalvefc'asing. '.flfor'ad- {through-,the 4bain2,|2,1.Q3l\;s the lever209.down justing'ethe amountlofpressure inftheline'. 12,- a Wardlyto the .dotted linepositionshown. at2091.;gauge:222zis-fprovided. lThisfgaugewis Yconnected This holds. the.limitswitoh ,201..closed.so..that, `with thefci-uot.`A 2031-loyf-affduot223;v ,.,as -rwill v be .explained'pmore fully hereinafter,y.as

.'Whenthe operatonpressestthe.Startinggbuttonsoon as the lbraclfzetZreaches operating-position of the machine, 4theJorai-:ket,82,ewhioh-carries gthe-solenoiclsj |10and. |1| (Fig. 11);may. be-enerthe Workis n iovecll` om doadngtposition togioper- ,gized. Nearthefbottom-of'thestroke. of the atineposition,-zasfw beadeseribed...moreazpartiou- .,:piston- 34,; theoam portion 54 of., the :am-` inem-;lar1y;;hereinafter. @JW e ebreek tz2feaches Yper 52 engages theroller#leandias.thegniston "operating @position l. theznm l. |16(.fEiefz-? ,garnichtaontinuesi.fto,;dese11d.;thefrollerf 2lgrides-nnprthe cam surface 54 onto the dwell portion 55. Thus, thelever 209 is rocked upwardly to assume the position shown in full lines(Fig. 6). This allows the limit switch 201 to open and the solenoid |10is deenergized with the result that the Valve |12 is closed. Thepressure fluid in going to the upper end of the cylinder` 24 must nowtravel through the restricted opening of the needle valve |86. Thus, thedownward movement of the piston 34 is slowed up. This prevents the upperdie from striking the hot workpiece with any force.

The decelerated movement of the piston continues as long as the roller2|8 is riding on the dwell portion 55 of the cam surface, and thebracket 2 I 6 is adjusted initially along the bar 2|2 so that thedecelerated movement will continue until just before -the upper dieengages the work. Then the roller 2|8 rides on the conical portion 56 ofthe cam track, moving the lever 209 upwardly to the dotted line positionshown at 209". The lever 209 remains in this position while the rolleris resting on the dwell portion 51 of the cam. In this position, thelever 209 closes the limit switch 208 which causes the solenoid |10 tobe reenergized, reopening the valve |12 and causing full pressure to beapplied to the upper die to hold the work securely against distortionduring the quenching operation. The closing of this switch also puts inoperation the first of 12 ing press from any suitable source. In thepress illustrated, the quenching liquid is supplied to the press througha pipe 225 (Fig. 2) which is connected to the base of the machine. Thebase is hollow and forms a sump. The quenching liquid is pumped out ofthis sump by a pump 228 which sucks the quenching liquid from the sumpthrough a pipe 226. The pump forces the liquid into a duct 230 which isconnected with a vertical duct 23| that is formed in a casting 232 whichis secured in the column 2|.

The quenching liquid is intended to ow from the duct 23| into a parallelduct 233 which is at the opposite side of the casting 232. There arethree ducts connecting the ducts 23| and 233 and each of theseconnecting ducts is controlled by a solenoid-operated valve. The threesolehold-operated valves are designated 235, 236, and

the timers controlling the flow of the quenching liquid to the work, aswill be described more particularly hereinafter.

After the work has been hardened and cooled to the desired degree, thesolenoids |46, |10, and |1| are deenergized as will be described moreparticularly hereinafter. The valves |14 and |15 then close and thevalve |43 then opens. The pressure fluid then flows from the line |20through the reducing valve and ducts |26, |21, and |28 into the upperend of the valve casing |22 to shift the shuttle valve |2I to theposition shown in Fig. 1l, the air exhausting from the lower end of thevalve casing through ducts |41, |49, and |5|, valve |43 and duct |44 tothe open air. With the shuttle valve |2| shifted to the position shown,the pressure fluid ilows on through the ducts |29, 69 and 10 to theunderface of the piston head 36. Simultaneously, upper end of thecylinder 24 is put on exhaust through ducts 61 and |5|, valve |43, andduct |44. Thus the piston 34 is returned to its uppermost position,moving the upper die clear of the Work.

During the upstroke of the piston 34, the duct 14, that leads to theupper end of the piston 60, remains on pressure from line |28 throughduct |23, reducing valve |60, ducts |6| and |55, check valve |56,differential relief valve |50, duct 12 and duct 14. However, as thepiston 34 ascends, the plate 4| (Figs. 3 and 4) which issecured to thepiston 34, engages the piston 60 and causes the piston 60 to moveupwardly away from the work, also.

In setting up the machine, it is desirable to jog the piston 34 up ordown through manual operation. For manual operation, the three-way valve|48 is moved to position to connect duct |41 with exhaust duct 281. Thusshuttle valve |2| is held inoperative in the down position shown in Fig.11. The movement of `piston 34 is then controlled by energizing ordeenergizing solenoids |46 and |1| as will hereinafter be described moreparticularly.

The quenching uid is supplied tothe quench- 231 respectively. They areof similar construction but their openings are of different sizes. The

opening of the valve 235 is the largest; the opening of the valve 231 isthe smallest; while the opening of the valve 236 is intermediate in sizebetween those of the valves 235 and 231. l

The valve 235 is shown in section in order to show the structure of theseveral valves. It has a valve member 24| that has an elongated stemthat extends into the solenoid 238, and this valve member controls theconnection between the duct portions 242 and 244 of the valve thatcommunicate, respectively, with the ducts 23| and 233.

The solenoids for operating the different valves are denoted at 238,239, and 240, respectively. When all three valves 235, 236, and 231 areopen there is a maximum iiow of thequenching liquid between the ducts23| and 233. By opening valve 235 and valve 231 while valve 236 isclosed, a different volume of flow of the quenching liquid between theducts 23| and 233 can be obtained. Other variations in volume of ow canbe obtained by making other combinations of open and closed valves, aswill be obvious.

The duct 233 is connected by a duct 243 with a trough 244 secured to thebase 20 of the machine beneath the plate H2. The quenching liquid flowsfrom the trough 244 upward through a screen 241 that is secured in thebottom of casting II2A and thence through a central opening 245 and aplurality of circularly arranged holes 246 in the casting H2 (Figs. 2and 4) into a central opening 246 and circularly spaced ducts 249 in theplate 82. Thence the quenching liquid ilows through an inner series ofspaced circularly arranged openings 250 and an outer series ofcircularly spaced holes 25| in the plate 8|. From these, the quenchingliquid flows upwardly through the teeth of the gear G to be quenched,underneath the back face of the gear through radially aligned slots 252provided in the upper faces of the rings 80, and through slots 253 cutinto the peripheral surfaces of the gripper segments 81. Thus the sidesof the teeth, back face, and bore of the gear may be hardened andcooled. Thence the liquid flows through the central opening 254 in theupper die 45, the central opening 255 in the plate 43, and circularlyarranged spaced openings 25S in the platev 4|. Thence the liquid flowsinto the space between the cam member 52 and guard 50, over the outsideof the guards 50 and 84 and'plate 82 through a screen 258 (Fig. 2) inthe upper face of the base 20 of the machine into the vase or sump ofthe machine. The overow of liquid in the sump is carried 01T through theopen upper end oi the trough 221 and the pipe iwl i? 123 229 :toz'theexternaltsource :iromswhichithealiquid @andparticularly,zmzdetetmmirigsthelppostcnzof is supplied to the: machine.Bhe :direction of tthefbnacgketigZ LGQIi--therrd12g( 1,6); it isidelowsof the'quencliingwliquidfaroundr .the work is issiralcle:V that`,theyxnoyements of itheapistonttbe fdenoted by. thearrows iniFig.-.4.emanuallyacontrolled;lbutginzthefnormal;operation In thequenchingfpress'.illustratedthefquencli- .5.tot'themachinezthemovements-otthisapistonzand ing operations'maybeeffected'in three-,successive...thefullgcycleof=operaticn:ofrthecfpresslarev autostages "The time`during which each stagaof smatie. ,I-A1selecto1knob128fWigs:1. and 7)-ispro quenching. takes placeY is determined loy'y the set- :FvidedI-whiehcan-be a`d=iusted manuallyV .to deterting ofla timer button. Thethreetimer-buttons smi-necW-hetherrtherfmachineistok voperate autoare denotedat 260,261, and 262, respectively (llig. -l' vvmatically or manually.This-1 selector-knob 230 1) The volumeof the quenching liquid that isto@entr-01sttheL-positiomof i'fhenthree-wayfV valve |48 ji-flow over theworkv-during-thediierent-stagesfof -f (Figs-11). =:fThe=-selector knobis secured tothe L harden-ing, is determined bythe setting-ofselector vff'front end'lofffasha-ftfZB II `which is journaled in the l'buttonswhich control the-operation `of the solefgfcolumn2Leardfingalbracket282'that-'is secured gnoids 238, 239; a1fid-2fl` (Eig.;2). i5 Jto'the-column, 'IotherearV end of the shaft28'l There are three selectorbuttons associated l"t1fi are--is-secured al cam oreccentric "283(Figsxfl "witheach'timer'to permit determiningwhatv01e an'd). IThiscatnfengages ai roller 284-which-is ume of quenchingj liquidn will `flow'over' the-work secured'onja"leye1i'285that'fis pivoted at oneendjduringthe stage of hardening controlled by-that throughjtheipin'2861on1the3casingiof" the threeparticulartimer. The selector buttons maybead-i320 "Way-valve L48. ""Thelever285 is adapted to engage l; justedto eitheron` or offA position If the three "the plunger' 288 vof-theValve, as the-cam'- 283, is rel:selector buttons ,associated with .aparticular yolyed ;Theplunger is spring-pressed outwardly v. timerare.all adjusted tothe on position,;thel1 fgtogholdfthe-yalveynormally'inthe automatic during thestage of. .quenching controlled bytha@'po'stipn, shown gdjagrammatja'llyV in'jFilg, 1 1, to particular timer,all `three of the solenoid-.opergccnnecttheiductsg |41'l 4 and l 49.Whenjthe .camis ated valyesn 235, 236, and 231 )(Fig." 2) .willbe,open,V:revolved, hoyl/eyei..the@ leve1;1?85 is swungabout and Y themaximumvolume oflquidwill flow over '3,' ,itspiv;ot 286 to press 'theplungerZtl inwardly `the work. If twcofthe selector .buttons asso-...tofconnectductj1,41 withl exhaust duct 289. ciated with aparticulartimerarein lthe fon j 'I ,hevshaft,28|, is of enlargedtldiameter,towardposition and the third, is. in the o i position, .its.front.end,andthepeisanarcuate slot V29l1=ut then the twosolenoid-operated.valvesfwhichlaxe part ,wayaround ...its i,periraliery, the ,bottom ,of vcontrolled by. the two fonbuttons-.twill.bepen which isfeecentric ofgthe, aXis-Jofthehaft. A and ithe third solenoidvoperated .valve will be sImrmally-Qpen-,limt-switchlLisrmounted in the closed, during the-particularistageof.luarderlirlg.3L fllumn Zllgorianr angler-plate. 292 ,in such positiont.controlled Zby thatparticular timer. .Hencadur- Atl-iatthe,plungerof.the limitswitchfmay engage ring that .particular stageofoperation. the-volume the recessed p0 1 t0n29|Lof thee Shaft 28E. When yof quenching liquid, Vwhich ilowsoyer the Work,lftheshaftf'liisilotated. fromthe position shown iwill be reduced as4compared `with the yolume 2in1 Egs. 7231x113;then,gnot.onlyis,the`three-,way owing durngfthestagewwhen all solenoid-@peic- Nyalvei 148.shifted topostion for .automatic operaatgdvalves ,are Open, H011 but)With29 [-.1818150 0105611. `vA `plfl'l.

The selector` buttons, that cooperate'withifhessmwihh:PTQiCCtSfrolvagonl';295.13121? SfSetimer 260,-aredenoted .at`263,.A 264, .and ..26 5, 4re- :.Qlllfed.JO-thezshaftf-ZB l ,.-and `whichiSl adaptedto J@spectively (Fig. 1). The selector buttons,thatcofzfflgge. p llzflfihi? siseurevdn the Column 2 ,bperate within@timer 26s,arevden0dat .zsllmserves @tollmitrotarymovementofthe-Shaft28|-268, andfZs, respectively. The.selectcr buttons, .Qnswayi 1h.1=h..the..mffwhmemay. he wired 'rthat cooperate with the timer262,;arefder1otedtat @@lectl'lltly t0 fllflmphsh 1 tS --fpullfose -1Smus 219, 21h-and 212,- respectively. girate@ dlafgrafnmamcauym'mg 12 .chof the selecforvbuttons 253,1251 (andino ,Thel threetimers, l.whichcontrolthc t1me of v fbhesolenoidngg Fi .7:72),wpperationaofthe-.threelstages,of thel quenching controls the Cpemtmn og loperation,sc are shown at the/.top'Of l,this diagram 2 I Eachoftheselector buttons 264,268 `and I con at 395, 5m), and 545* Theselmersmaybe of that' Vays employedliin ,therrunctioning ofthe ithe operation ofthesoleno1d-246- -V .111 the set-up Shown in Fig 1, the seleclpr butfie'mss Sfalso; Shown 'Qn"the"'t0p'1me of the dla" u I T, ,t, H d,efnextdrnpoivtantparts Shown.diagrammatically *find 272' are-lume fdPos1 1on1; fu areaghelolenoidsl 238,= 239,arid 246 which control c work;seefFigs 2. Below these,f,are four rela S1365, ',lows`through,thethree;.solenoidoperatedvalves y 65,515, andrl.,-.Belowtharelays-365 and: 465 :235,236,1and 231 toquenchtheworkdrastically, exime ,elaysrand azwhe,belowthemelays during the StageOf'hald'en-ng' CQntmud-byk-lei5r@11555alie.lllufratGdA-Idiagrammatically the timerZSL/a reducedvolume; of quenchmglQl-lld three groups of Selectokandmer buttons comslows.- over,the.work.:through#thefsolerloideopernedwimm.33h@5p3,1191.atlthedlft4 hand Side of f ated Valves2351and231:to'graduallyccolrthe'work ontlofgghe-malchmeiseepig1 Belowthese gin such :way .,astotobtain 4the.,desiredrfrxiolecllftl? are 3illustratedtheecadditional; relays 405, f 446, :Structure: farldf'dulng-the staserof, hardening-wf anda. Below ,thesaareishown ,theJseveral limit `the -timer 262, a somewhat vincreased vclume.-;'.0f f.Fwitelfies, 35,8;5366gg2013 20.6,a11d 29|,the starter v-oi1 fflows.' overtheworkcthroughrthe;;so1enoid uti-,Qn 32u, and heit-,GUY bui-,501174323Belowjhe :operated Valves 235 Vand `2336 itc-'cool 'theniizoikiswltqhesllandi346@efshOWn the'SOleIlOdS rapidly" t0, 'a temperatureWhefe*taneadyebe 1.1, iflufand V1.0 (Fg- 111) Igwllch rcontroLthehandled'by the operatorf ffixriovement .chiches-piston :1134. @Below,..these. :.are

As a1ready-stated,=in settingsupfthe.-machinet%shcwni contrqlzlele Land:thezmotori which drives the quenching oil pump 228 (Fig. 2). Below thelimit switches 201, 206, and 29| are shown the controller 345 and themotor 96v (Fig. 2) which drives the mechanism for moving the bracketfrom loading to operative position and vice versa. The several relays310, 305, 465, 5|5, 555, 385, 352, 405, 440, and 390 may be of an7standard or suitable construction. Likewise, the controllers 345 and 321may be of any standard-or suitable construction.

Assuming that the selector knob 280 (Figs. 1 and 7) has been moved toautomatic position, then the limit switch 29| will be in a positionshown in Fig. 12, connecting the lines 300 and 30|. This causes the coil304 of the relay 305 to be energized, causing the switch arms 306, 301,and 303 of the relay to assume the positions shown in Fig. 12. Thecircuit to the coil 304 is from the main line L1 through the lines 3|0,3| and 300, limit switch 29|, lines 30| and 309, coil 304, and lines3|5, 3|6, 3|1, and 3|8 to main line L2.

The machine is now ready for operation. When the operator pushes in thestarting button 320, a circuit is made from the main line L1 through theline 32|,starter button 320, line 322, stop button 323, line 324, coil325 of controller 32,1, line 326, switch arm 306 of relay 305, and lines3|6, 3|1, and 3|8 back to main line L2. This energizes the coil 325 ofthe controller 321, pulling in the switch arms 330, 33|, and 332 of thiscontroller and starting the motor 335 which drives the pump 228 (Fig. 2)for the quenching fluid.

Simultaneously, the coil 340 of controller 345 is energized, causing theswitch arms 34|, 342, and 343 to be pulled in, to start the motor 96which operates the mechanism which swings the bracket 82 (Fig. 2). Thecircuit to the coil 340 is from the main line L2 through the lines 3|8and 341, the limit switch 348 (Fig. 5), the line 349, the coil 340, theline 350, the switch arm 35| of relay 352, the lines 353, 354, 355, and322, the start button 320, and line 32| to line L1. The switch arm 35|is at this time closedbecause the coil 351 is at this time energized andthe coil351 is at this time energized because the limitI switch 360 isat this time held closed by the angle plate 88 (Fig. 2) carried by thebar 95. The circuit to the coil 351 is from the main line L1 through thelines 310, 3||, 36|, and 362, the limit switch 360, the line 363, thecoil 351, and the lines 364, 3|6, 3|1, and 3 i 8, to the main line L2. v

Simultaneously with the energizing of the coils 325 and 340,respectively, the coil 31| of the relay 310 is energized. The circuit tothis coil is from the main line L1 through the line 432|, the startingbutton 320, the line 322, the stop button 323, the line 312, the coil31|, the line 314, switch arm 306 of relay 305, and lines 3|6, 3|1, and3|8 to main line L2. With the coil 31| energized, the switch arm 315 ofrelay 310 is pulled in, and the switch arm 510 of this relay is pulledout. The starting button 320 musi-l be held by the operator in longenough for the bracket 82 to start from loading into working position. y

As soon as the bracket starts to move, the limit switch 380, which hasbeen held open by the pin |16 (Fig. 5) is released, and this limitswitch, which is normally closed, closes. A circuit is then made to thecoil 38| of the relay 385 from the main line L2 through the lines 3|8and 341, the limit switch 380, the line 383', the coil 38 the line 386,the switch arm 381 of relay 390, the .lines 388, 389, 39|, and 392, theswitch arm 393, the

-the lines 400 and 40|.

16 the lines 354, 355, and 322, the starter button 320, and the line 32|to the main line L1.

The continued energization of the coils 31| and 38| is necessary to keepthe coils 325 and 340 of the controllers 321 and 345 energized, that is,to keep the motors 335 and 96 running.

After the starter button 320 is released, the circuit to the Acoil 31|is maintained from the main line L2 through the lines 3|8, 3|1, and 3|6,the switch arm 306 of relay 305, the line 314, the coil 31|, the line312, stop button 323, the lines 355 and 354, the switch arm 315 of relay31|),the lines 396 and 394, switch arm 393 of timer 395, the lines 392,39|, and 389, the noW closed switch arm 391 of relay 385, the line 30|,the limit switch 29|, the lines 300, 3||, and 3|0 to the main line L1.The circuit to the coil 38| is maintained, after the start button hasbeen released, from the main line L1 through the lines 3|.0, 3||, and300, the limit switch 29|, the line 30|, the switch arm 391 of relay385, the line 388, the switch arm 331 of relay 390, the line 386, thecoil 38|, the line 383, the now-closed limit switch 380, the line 341,and the line 3|8 back to the main line L2. The circuit to the coil 325is maintained from the main line L1 through the lines 3|0, 3||, and 300,the switch 29|, the line 39|, the switch arm 391 of relay 385, the

.lines 389, 39|, and 392, the switch arm 393, the

lines 394 and 396, the switch arm 315, the lines 35,4 and 355, the stopbutton 323, the line 324, the coil 325, the line 326, the switch arm 306of relay 305 and the lines 3|6, 3|1, and 3|8 to the main line L2. Thecircuit to the coil 340 is maintained from the main line L1 through thelines 3|0, 3||, and 300, the limit switch 29|, the line 30|, the switcharm 391, the lines 389, 39|, and 392', the switch arm 393, the lines 394and 396, the switch arm 315, the lines 354 and 355, the stop button 323,the line 312, the coil 31|, the line 314, the switch arm 306, and thelines "31s, si?, and 3|8, back to the main une L2.

When the bracket 82 reaches working position, the pin |16 (Fig. 5)carried by the crank-plate |00 strikes the plunger of the limit switch348 causing this limit switch to break the connection between the lines341 and 349 and to connect The breaking of the connection between thelines 341 and 349 stops the bracket motor 96 While the making of theconnection between the lines 400 and 40| energizes the coil 404 of relay405, causing the switch arms 406 and 401 to be closed. The circuit tothe coil 404 is from the main line L1 through the lines 34|0 and 3||,the coil 404, the line 40|, the now- ."shi'fted limit switch 348, andthe lines 400, 341,

and 3|8 to the main line Lz.

This energizes the solenoids |46, |10, and 1| (Fig. 11). The circuit tothe solenoid |1| is made from the main line L2 through the lines 4|6 and4|1, the solenoid |1|, the lines 4|8 and 4|9, the switch arm 401 ofrelay 405, the line 354, the switch arm 315 of relay 310, the lines 396and 394, the switch arm 393, the lines 392, 39|, and 389, the switch arm391, the line 39| the limit switch 29|, and the lines 300, 3||, and 3|0to the main line L1. The circuit to the solenoid |46 is from the mainline Lz through the lines 4|6 and 4I1, the solenoid |46, the line 422,the switch arm 301, the line 4|9 and thence as described for thesolenoid |1| to the main line L1. The circuit to the solenoid |10 isfrom the main line Lz through the lines 4|6 and 4|1, the solef lines 394and 396, the now closed switch arm 315, u noid |10, the line 43|, thelimit switch 201, the

17 line 432, the line 4| 9, and thence as described for the solenoid |1|to the main line L1.

When the solenoids and |1| are energized,

the valves 12 and |13 (Fig. 11) are opened, andv when the solenoid |46is energized, the valve |45 is closed. This permits the compressed airto be supplied to the upper end of the piston 34, forcing the pistondownward to operating position. The valve |45 is normally spring-pressedto open position so that if the power should fail the piston 34 willreturn to its upper position. This safety feature prevents injury to theworkman in case of power failure.

As the piston 34 descends, the cam 52 (Fig. 6) holds the limit switch201 closed until the piston is near the end of its downward stroke. Thenthe roller 2|8 rides up the beveled nose 54 of the cam surface onto thedwell portion 55. This causes the lever 209 to be moved to itsintermediate position, as already described, and permits the limitswitch 201 to open which deenergizes the solenoid |10 (Fig. 11) andallows the valve |12 to close. This shuts orf the ow of the pressurefluid through the line |84 and causes the pressure fluid to flow to theupper face of the piston 34 through the restricted opening of the needlevalve |86. Thus, the speed of descent of the ram is slowed up.

When the piston 34 approaches the end of its downward stroke and theupper die 41 (Fig. 3) is in operative engagement with the work, theroller' 2|8 (Fig. 6) rides up on the bevel portion 56 of cam 52 onto thedwell portion 51. This causes the lever 209 to close the limit switch206 (Figs. 6 and 12). This energizes the coil 436 of the relay 440. Thecircuit to this coil 436 is from the main line L1 through the lines 3|0,3| and 36|, limit switch 206, lines 438 and 439, coil 436, and lines44|, 3|1, and 3|8 back to main line L2. This closes the switch arms 443and 444 of relay 440.

The closing of switch arm 443 reestabllshes a circuit to solenoid |10(Fig. 11), and valve |12 is opened again. Thus full pressure is againput on the upper face of piston head 36, causing the L upper die 41 toclamp the work firmly and securely. The circuit to the solenoid |10 isfrom main line L2 through lines 4|6 and 4|1, the solenoid |10, lines 43|and 431, switch arm 443, lines 446, 432, 4|8, 4|9, switch arm 401 ofrelay 405,

line 354, switch arm 315 of relay 310, lines 396 and 394, switch arm393, lines 392 and 389, switch arm 391 of relay 335, line 30|, limitswitch 29|, and lines 300, 3H, and 3|() to main line L1.

The closing of switch arm 444 of relay 440 establishes a circuit to thetiming mechanism of timer 395, the circuit being made from the main lineL2 through the lines 3|8, 3|1, 461, and 45|, the mechanism 450, thelines 452 and 453, the switch arm 308 of relay 305, the line 454, theswitch arm 444 of the relay 440, the lines 46|, 446, 432, 4|8, and 4|9,the switch arm 401 of relay 405, and the line 354 back to the main lineL1 in same manner as the circuits to the solenoids |46 and |10. The timeof operation of thetimer 395 is determined by the setting of thepotentiometer switch 260 (Figs. 1 and 12) which is connected to thetimer by the lines 458 and 459.

When the switch arm 444 of relay 440 is closed, the coil 460 of relay465 is also energized. The circuit of this coil is made from the mainline L1 through'v the lines 3|0, 3H, and 300, the limit switch 29|, theline 39|, the switch arm 391, the lines 389, 39|, and 392, the switcharm 393, the lines 394 and 396, the switch arm 315, the line 18 354, theswitch arm 401, the lines 4|9, 4|8, 432, 446, and 46|, the switch arm444, theline 454, the Switch arm 308, the line 453, the switch arm 448,the line 466, the coil 460, and the lines 461, 3|1, and 3|8 back to themain line L2.

This pulls in the switch arms 468, 469, and 410 of relay 465. Thuscircuits are made possible to the solenoids 238, 239, and 240 (Fig. 2)that operate the valves 235, 2 36, andr 231, respectively, which controlthe supply of the quenching iiuid to the work. Whether these circuitsare actually closed or not depends on whether the selector buttons 263,264, and 265 (Fig. l) are adjusted to their on or off positions. Thecircuit tothe sole.- noid 238 is made from the main line L2 through thelines 3|8, 3|1, 3|6, 3|5, and 419, the solenoid 238, the line 430,switch arm 468, the line 48|, the manually adjustable switch arm 263, ifthat switch arm is in the on position, the lines 483, 404, and 485 tothe main line L1. In similar manner, the circuits to the solenoids 239and 240, respectively, are made if the manually operable switch arms 264and 265 are in the on" position, the switch arm 264, when in the onposition, connecting the line 484 with the line 419 through the solenoid239, line 481, switch arm 469 and line 490, while the switch arm 265when in on or closed position connects the line 484 with the line 419through the solenoid 240, line 488, switch arm 410 and line 49|. If oneof the switch arms 263, 264, or 265 is left in its off position, thecorresponding solenoid 238, 239, or 240 is not energized, and thecorresponding valve 235, 236, or 231 (Fig. 2) is not opened during thetime of operation of the timer 395. v

Thus the volume of oil flowing to the work during the operation of thetimer 395 depends on the setting of the selector buttons or switch arms263, 264, and 265. As shown in Fig. l, as already stated, all three ofthese switch arms are in the on or closed position, so during operationof timer 395, all of the valves 235, 236, and 231 are open and themaximum volume of quenching liquid flows over the work.

After the timer 395 has functioned for the period of time determined bythe manual adjustment of the potentiometer button or switch 260 (Figs. land 12) the timer mechanism 450 operates to break4 the connection of theswitch arms 393 and 44B with the lines 394 and 466, respectively,allowing these arms to make engagement with the terminals 495 and 496.This causes the circuit to be made to the timer mechanism 50| of timer500, and sets that timer mechanism in operation. Ihis circuit; is fromthe main line L2 through the lines 3|8, 3|1, and 461, the line 502, thetimer mechanism 50|, the lines 503 and 501, the switch arm 443, the line453, the switch arm 308, the line 454, the switch arm 444 of relay 440,the lines 46|, 446, 432, 4|8,` and 4|9, the switch arm 401, the line354, the switch arm 315, the lines 396 and 509, the switch arm 5|0, thelines 5| 39|, 5|3, and 389, the switch arm 391, the line 30|, the limitswitch 29|, the lines 300, 3| and 3|0 to the main line L1.

Simultaneously, the coil 506 of the relay 5|5 is energized, this coilbeing connected at one side through the lines 5|6, 461, 3|1, and 3|0with the main line L2, and being connected on the opposite side with theline`L1 through the line 505, switch arm 5|4, and line 501 and switcharm 448 in the same manner as already described for the circuit to thetimery 50|.v The energized coil 506 pulls in the switch arms 5|1, 5|6,and 5|9 of relay 5|5. These make circuits to the so1enoids 238,

239", and: 240, respectively (Figs..2 and 12), if the manuallyadjustableswitch arms 201, 268,. and 269'; respectively (Figs. 1 and. 12) areclosed.

Thus, if the switch arm orbutton' 261 isvin on or closed position, acircuit is closed' from main line L1 through lines`485, 484:,.and 529,switch arm 2611, line 530, switch arm 511, lines 53|v and 523-,solenoid. 238, lines 419, 3|5, 3|9, 3|1, and 318Y to main line L2. In.similar manner if the switch arm-or buttonV 268-isin on or closedposition, a circuit is made through solenoid 239between line 484, whichis connected with main line'Li, as just described, and line 419, whichis connected, as just. describedwith main line L2, this circuit beingthrough switch arm-208; line 532, switch arm |8 l of relay 5|5, lines533 and 534, and solenoid 239;

Likewise, if switch arm or button 269 is in on or. closed. position, acircuitV islmade through solenoidy 240:between. line 494 and line 41-9,this circuit being. through switch arm.` 269, line- 535, switch'arm'5|9of relay 515, lines- 536 andv 531 and solenoid 240;

Thus, during operation of the timer 500, the volume of quenching Vliquidowing over the work is determined by which of the switch; arms 261, 268,and 269are in the on or'closed position. In the setup1i1iustrated` inFig. 1, only the switch arms 261 and 269 are in the "oniy position, andtherefore during operation of. timer 500, only the solenoids 230` and240'wil1 be energized and only the valyes.y 235 and4 231 (Fig. 2). willbe open.

The. length of time. of operation of the timer 500,. isgoverned by thesetting of. the potentiometer switch or selector button 26|. (Figs. 1and 12). This switch is.' connected with the timer' mechw anism. 50| bylines 525l and 526.

After the timer 590 has'functioned for the predetermined. periodoftime,.the timer mechanism 50 operates to break the connection of theswitch arms'5l0 and 5|4y with the'lines 509 and` 505, respectively,allowing these arms to make contact with the terminalsV 540i and 54|,respectively. The contact of switch arm 5.44` with terminal 54| closes acircuit to the timer mechanism 544: of the timer 545`4 and sets thattimer' mechanism in operation. This circuit is from the main line L2.through lines 3|8, 311, and 461., thev timer mechanism 544 of timer 545,lines 545. and 541, the now shifted switch arm 5|4 of timer 500, theline 501, the now shifted switch arm 448 of timer 395,.the. line 453-,the switch. arm 308 of relay 305, the line 454, the switch army 444 ofrelay 4,40, the lines 45|, 446-, 432, M8, andA 4|9, the switch arm 401of relay 405, the line 354, the switch arm 315 of relay 31.0,. the linel396, the switch arm 549 of timer 545,- the lines 39|, 513, and 389, theswitch arm1391 of relay 385, the line 30|, the limit switch 29|, and thelines 300, 3| i, and 3H) to the main lineLL Simultaneously the coil 552ofthe relay 555 is energized, this coil being connectedv at one sidethrough the line 553v and` switch. arm 559 with the line 541 and beingconnected on the other side through the line-554 and line 5I0 with theline 461, the circuit to the coil 552 being otherwise. made as describedfor the timer mechamsm. 544.;

The energized. coil 552pu1ls in the/switch arms 55.1., 558, and 5590irelay 555. Circuits are thereby made towhichever ofthe solenoids 233,239, and.; 240. (Figs. 2 and 12)l it is. desired be energized atthisstage of the; hardeningI operation, the selection depending uponthesettingsoi the selectorbuttons-210, 21|, and 212l (Fig. 1).

If the; selector button..210 is adjusted, for in.-

stance, to its oni position', a circuit is closed between the main lineL1 and one side ofv the solenoid 230 through thelines 485 and 550, theswitch arm' 210, the line 56|, the-switch arm 551, and the line 528 Ifthe switch arm or selector button 21| is in its on or closed position, acircuit is completed from the line L1 through the lines 485 and 484, theswitch arm 21|, the line 562, switch arm 558, andline 534, to one sideof the solenoid 239. If thefselector button or switch arm 212 is in itson position, a circuit is made fromthe main line L1 through the lines485 and 494, the switch arm 212, the line 564, the switch arm- 559, andthe line 531 to one side of the soienoid 240. The opposite sides of theseveral solenoids238, 239, and 240 are connected, as already described,to the line la through the lines 419, 3|5, :A9, 3|1, and 3|8.

In the set-up illustrated in Fig. 1, the selector buttons or switch arms210 and 21| are in the on position, while the selector button 212 is inthe off position. Therefore during operation of the timer 545', thesolenoids 238 and 239 are energized, while the solenoid 240 remainsdeenergized. The valves 235 and 236 (Fig. 2) will, therefore, be" openduring operation of the timer 545, while the valve 231 will remainclosed.

With the set-up illustrated in Fig. 1, therefore, the volume of.quenching liquid. flowing to the work will be greater during the periodof operation of the timer 545 than during the period of operation of thetimer 500, but will be less than during the period of operation of thetimer 395'. With the set-up' illustrated in. Fig. 1, then, the Work willbe iiooded with. the maximum volume of quenching liquid for a perioddetermined by the setting of the potentiometer switch or button 260,then a reducedv volume of liquid will iiow over the work fora period oftime determined by the setting of the potentiometer switch or button26|, and finally a somewhat increased volume of liquid, as compared withthe rate of ow during the second stage, will iiow over the work forwhatever period is selected through setting of the potentiometer switchor button 262.

The potentiometer switch is connected to the timer mechanism 544 oftimer 5115 by the lines 555 and 556. When the timer mechanism trips, atthe end of the period for which the button 252 is adjusted, theconnection of the switch arms 539 and 550 with the lines 396 and 553,respectively, is broken, allowing these arms to make contact with theterminals 561. and 568.

The circuits to the solenoids |46, |10, and 1| (Figs. lland 12) have`been maintained during the successive operation of the timers 395, 500,and 545 by connection of the switch arms 393, 510, and 549 successivelywith the lines 394, 509, and 396, respectively. When the switch arm 549is moved, therefore, to break the connection between the lines 390 and39|, the solenoids |46,

|11, and |10 are deenergized. The circuit to the coil 325 is alsobroken, stopping the pump drive motor 335. At the same time, the circuitto the coil 31| of relay 310 is broken,..causing the switch arm 315 tobreak the connection between the lines tle valve |2| back to theposition shown in Fig. 11, as previously described. The piston'34 is,therefore moved to its upper position, disengaging the die from thework. Asthe piston ascends, the lever arm 209 (Fig. 6) is rockedclockwise releasing the pushrool 208 of the limit switch 206, and thislimit switch opens. When the piston 34 reaches its uppermost position,the lever arm 209 closes the limit switch 201.

As soon as the piston 34 reaches its uppermost position, the pistonhead36 strikes the angle plate 16 (Fig. 3) causing the arms 93 (Figs. 2 and3) and arms 9| to be moved upwardly, causing the bracket 82 to be liftedoi its seat |'|2 (Figs. 2 and 4) and causing the angle plate 88 to closethe limit switch 360 (Figs. 2 and 12). The closing of the limit switch360 energizes the coil 351 of relay 352 in the manner already described,thus pulling in the switch arms 582 and 35| of this relay. This actionenergizes the coil 515 of the controller 345, causing the switch arms516, 51.1, and 518 to be pulled in, starting `the bracket motor 96 in adirection to cause the bracket 82, which carries the work, to move outtoloading position. The circuit to the coil 515 is from the main line L2through the lines 3|9 and 341, the now-closed limit switch 380, the line580, the coil 515, the line 58|, the now-closed switch arm 582 of relay352, the line 51|, the switch arm 510, the lines 5|3 and 389, the switcharm 391, the line 30|, the limit switch 29|, and the lines 300, 3| I,and 3|0 to the main line L1.

When the bracket reaches the out or loading position, the pin |16 (Fig.5) carried by the crank plate engages the normally closed limit switch380 and forces this switch open, stopping the bracket motor 96, for thisbreaks the circuit to the coil 515. The work is now at loading positionand the Whole machine is stopped. To restart the machine, it isnecessary again to press the startv button 320.

If for any reason, the'bracket motor 96 should fail before the bracket82 has reached its full out position, the bracket will stop, but if thepower should come back on again, the bracket will not restart, becausewhen the power fails, the circuit to the coil 38|' of the relay 385 isbroken, the switch arm 391 opens, and the circuit to the coil 38| cannot be made again without pushing in the start button 320. Thus theoperator of the machine is absolutely protected against injury .duringoperation of the machine.

In setting up the machine, it is necessary to adjust the position of thebracket 2|6 along the rod 2|2 (Fig. 6) so as to determine the point inthe down stroke of the piston 34 where down stroke will end and fullpressure bev put on the work. In this simultaneously, the point wherethe rate of the piston is slowed down to prevent the upper die fromstriking the hot workpiece at high speed is determined. In order'toadjust the piston stroke, the operator first throws the selector. knob280 over to the manual operating position. This causes the limit switch29| (Figs. 7 and 12) to break the connection between the lines '300 and30| and make connection betweenthe lines 3|| and 59.6. The breaking ofthe connection between the lines 300 and 39| deenergizes the relay 305,preventing the starting of the pump motor 335 and the closing of relay310, l f 1. In the normal non-working position of the press, the vpiston3 4 Fig; 3) is in its uppermost position and the bracket 82` in its outor loading position. Before thestrokeofthe Vpiston can be 22 adjusted,then, it is necessary to move the bracket B2 to its in or operativeposition.

In the up position of the piston, the limit switch 360 is held closed bythe angle plate 09 (Fig. 2) and the coil 351 is energized, closing theswitch arms 582 and 35|, as already described with reference to theautomatic operation of the machine. When the starter button 320 ispushed in, then, a circuit is made from main line L1 through line 32|,starter button 320, lines 322, 355, 354, and 353, switch arm 35|, line350, coil 340 of controller 345, line 349, limit switch 348, and line 3|8 to main line L2. This energize-s the coil 340 of controller 345 topull in the switch arms 34|', 342, and 343 and starts the bracket drivemotor 96. Since switch arm 315 of relay 310 is now open, the starterbutton must be held closed in order for the bracket-motor 96 to run andmove the bracket 82 toward operative position.

As the bracket moves into operative position, the pin |16 (Fig. 5)rotates away from the plunger of limit switch 380, permitting this limitswitch to close. When the bracket 82 reaches operative position, the pin|16 strikes the plunger of limit switch 34B and shifts this switch todisconnect lines 341 and 349 and connect lines 400 and 40| as alreadydescribed.

In order that the piston 34 may descend, the valve |45 (Fig. 11) must beclosed and the valve |13 must be open, that is, the solenoids |46 and|1| must be energized. When the piston 34 is in its up position and thebracket. 82 is in its in" orworking position, the coil 404 of relay 405is energized, a circuit to this coil being made from the main line L1through the lines 3|0, 3| the coil 404, the line 40 the now-shiftedlimit switch 346, and the lines 400, 341, and 3|8 to the main line L2.This causes the switch arms 406 and 401 of relay 405 to be closed. Thus,when the piston 34 is in its up position and the bracket 82 is inworking position, the solenoid |46 is energized, the circuit to thesolenoid being made from the main line L2 through the lines 4|6 and 4|1, the solenoid |46, the line 422, the switch arm 301, which nowconnects lines 422 and 600 because coil 304 is deenergized by shift oflimit switch 29| (Figs. '7 and 12) to manual position, the line 600, theswitch arm 599 of relay 390, the line 604, the now-closed switch arm 406of relay 405, and the lines 3| i and 3| 0 toA main line L1.

If the starter button 320 is at this time closed, circuits are also madeto the solenoids 1| and |10. The circuit to solenoid |1| is from themain line L1 through the line 32|, the starter button 320, the lines322, 355, and 354, the switch arm 401 of relay 405, the lines 4|9 and4|8, the solenoid |1|, the line 4|1, and the line 4|6 to the main lineL2. The circuit to solenoid |10 is from main line L1 to line 4|8 exactlyas just described for solenoid |1| and thence through line 432, limitswitch 201, line 43|, coil |10, and lines 4|1 and 4|6 to main line L2.

With the solenoids |46, |10, and |1| energized, the valves |14 and |13(Fig. 11) are opened and the valve |45 is closed, so that the piston 34descends rapidly, and will continue to so descend until roller 2|3 ofbracket 2 I6 strikes the portion 54 of cam 52. The operator maydetermine where he wants to set the bracket 2|9 (Fig. 6), which carriesthe roller 2| 8, by watching the light 590 (Fig. 12) which may belocated at any convenient point on the machine. This light is soconnected as to be operated by the limit switch 206 (Fig. 6) when thatlimit switch is closed, which means thatthe-ligntf'isffillnminatedwhen.` the piston 34 is at the selected-end:ofits'down stroke when full pressurexis puton theupper die. l'Ehecircuit to the lamp is made from the main line L1 through the lines3.13, 31|, and 361|, the limit vswitch 2156 the'v lines 436 and'439, thelight 599, the line- 591', the now-shifted switch arm3|16 of relay 395,and. the linesY 31| 6, 31|1', and 1MB` to' the main'l line L2;

ShouldA the operator desire to stoprthe4 downward descent of thezpiston34. at any point, he simply releasesthe start'button 3211. This breaksthe circuitsto the solenoids. |1r and |1I', allowing the valves |14 and|13.Y (Fig. 11) to close, shutting oli the supply ofthe pressure iiuidto the top' side of the pistonhead. 36. The solenoidv |46 remainsenergized, however; that is, the valve |45k remains vclosed'. The piston34k will, therefore, settle slowly until the pressure on the under faceof the piston head 36 brings the piston toa stop.

If the operator desires to bring the piston to a quick. stop, he notonly'releases the start' button 321|, but heY pressesin thev stop button323. This causes the coil 595k of: the relay 396' to be energized;shifting the switch arm 5.99' of that relay and breaking the circuit tothe'solenoid. |46'. This causes the solenoid tor .be deenergized,allowing the valve |45- (Fig. 11)` to open, thus putting the upper sideofthe. pistonhead 34-onex haust.

The circuit t-o the coil 595 is. from the main line Li through the lines3|0.1and131||, the-limit switch 29|, which is now inthe manual positionconnecting, theline=3|| with the line 596, the line 596, the stop button323, the line 5911, thev coil 595:, and the lines 44|', 3|1, and 3|@ tothe main line L2. Thus, as stated, the switch arm 539 of the relayl 390`is shifted and the switch arm 598 isclosed.

If the operator desires to return the piston 34 to its up position, hesimply continues to hold his iinger on the stop button 323. When thepiston reaches uppermost position, the angle plate 9S contacts andcloses limitswitch 360 (Figs. 2, 3, and i2), thus making a circuit tothe coil 351' of relay 352'. This circuit is made in the same wayasalready described for the automatic operation of the machine. Thiscloses the switch arms 582 and 35| of the relay.

If the stop button is held in long enough, a circuit is made from themain line L1 through the lines 316 and 3'|'|, the limit switch 29|, theline 596the stopy button 323, the line 591, the line 602, the switch arm598, the lines 603, 388, 389, and 5l3, the switch arm 510, the line,51|, the switch arm 582, the line 58|, the coil 515 of the controller345, the line 580, the now-closed limit switch 386, the line 341, andthe line 3|8' to the main line L2. This starts the bracket motor 96(Figs. 2 and 12) and causes' the bracket 82 to be swung out to loadingposition, so that the operator can position or remove, the workpiece.l

By pressing the starter and stop buttons, then, the operator canmanually control the operation of the press, and' can jog the-piston 34up or down to adjust the bracket 2 6 very precisely along the rod 2 2 inaccordance with thefheight and type of work to be hardened.

l litv will be obvious that the quenching press of this invention may beemployed in the hardening of various articlesL For each dierent job, anupper and a lower die andan expander ofv suitable shape and size-will beemployed. Figures 9 and 10 illustrate; the, type ofv holding mechanism.which 24 might he employed. inV the` hardening; of' a1 well known.design ofintemal gear I. This'gear hasl internal; teeth 6 I94 at itsperimetery and'vv integral therewith and spaced: radially. inwardlytherefrom a circular. bearinglportion 61| which is'connected' with thetoothed portion 6|9 by aweb 612.

In a gear of this type itis necessary not only to hold' the toothedportion 6 9 against distortion but also to hold the bearing portion 6||against distortion. For this purpose, two different sets of gripperisegmentsy and two different expanders are employed. The gripper segmentsof one set are denotedat 6|5. andv the gripper segments of thev other.set at 616. The lower set of gripper segments 6|6. are shaped to haveexternal surfaces' to about: the tips of' the teeth 6|9 and" to have.upper surfaces on which the web portion 612i ofl theVv gear may rest.The gripper segments 615 ofthe upper set are adapted to engage at theirperipheriesthe bore of the bearing portion 6| |A of; the gear. Thelatter segments are connected to the segments 6|6 by screws 6|1 whichpass through slots 6|8in,the segments 615 and which thread: into thesegments 6|6`. The segments 6|5l are guided in their radial movements onthe segments 6|6V by the screws 6|1 and by dowelpins 6|4 that aresecured in the segments 6 I6 and that passthrough-.radial slots 620formed in theiunder faces ofthe segments 6|5.

Forexpanding the segments 6|5 to engage the internal bearing surface 6||of the gear anexpander 625 is provided. This expander is threaded. onthe-nose ofthe plate 6 I l As'in the previouslydescribedy embodimentfofthe invention, this expander 625 has a tapered conical nose whichengages the internal` conically-bored surfaces of the grppersegments 6|5to force these segments outwardly, when the ram. 34 is lowered, thusholding the bearing surface 6| |l of the gear against distortion duringthe hardening operation.

The expander segments 6 I6 areK operated by an expander 630, Theexpander 630 is intended to have limited axial movement with referenceto the-expandervr 625. For this purpose, stop-pins 63| are providedwhichthread into the expander 630 and are secured therein by set'screws 632.The heads 633 of. thesewpins 63| are adapted to seatv in recesses 634formed in the nose of the expander 625; Coil .springs 635, whichsurround the pins 63| and are-seated in recesses 636 in the expander-636and are adapted to engage the lower end face off the expander625, serveto normally'press the expander 630 away from the expandery 625tothelimit permitted by the heads 6331y of the.pins-63|:.

For holding the upper face of the work against distortion during. thevhardeningy operation an upper diev 643 of suitable shape is provided.This is secured. in any'suitable manner to a plate 64| which in turn isfastened to the plate 4|. For

holding the lower surface of the toothed portion 6|9 of the gear againstdistortion during hardening, a4 suitable lower' die 642 is provided.This is securedl in any suitable manner to a ring 643 which in turn issecured in any suitable manner to the*v bracket platef 82. The plate 643has a plurality of` circumferentially spaced openings-6,45 near its.periphery and a second set of circularly arranged equi-spaced openings646 closer to its center.

In suitable circular recesses in the upperV face of, the plate 6.43are/mountedtwo rings 641 and 648i (Figs. 9 and 10)=. These rings' are'provided with', holes 649 and650, respectively, whichv communicate with.they holes 6451 and 646' in the platel

